Telephone-exchange system.



0.1. epodnum. TELEPHONE EXGHANQE SYSTEM. APPLICATION FILED SEPT. I I, ISIS.

Patenwd- Jan. 1, 1918.

4 /n v 'en for: (Charles .L. Goodrym;

UNITED STATES rnnr OFFICE.

CHARLES L. GOODRUM, or BROOKLYN, NEW X033, Assmnon 'ro WESTERN ELECTRIC GOMPANY, INCORPORATED; OF NEW YORK, H. Y., A QQBPORATION OF NEW YORK.

TELEPHONE-EXCHANGE sycam- Patented Jan. 1,1918.

Application filed September 11, 1918. Sex-10.1180. 119,508,

To all whom it may concern:

Be it known that I, (lrmnmzs L. Goounn'i a citizen of the United States, residing at Brooklyn, in the county of Kings and State of New York, have invented certain new and useful In'iprovement's in Telephone-Exchange Systems, of which the following is a full, clear, concise, and exact description.

these Selectors, it is found that the desired line at the connector busy. Heret-ofore, in such event, the calling subscriber received a busy signal and had to replace his receiver, whereupon the said switches wereall auto nlatically restored to their normal positions.

The object of the present invention is the provision of means which will make it nu necessary to release a connection when the desired line at the connector is busy. In the present embodiment of the invention, when the switch finds that the desired line is busy, it will. wait in operative relation to such line under the control of an impulse device. When the desired line becomes idle, the subscriber, by again operating the calling dial, may he placed in talking relation with thedesired line. i

The drawing represents diagrammatically a telephone system employing the present invention. The finder and selector switches of this system have been indicated by fixed terminals and brushes which are of a type comn'ionly employed in these switches.

It is believed that the present invention will best be described by tracinga connection over the system.

Referring to the drawings, A. represents the snl'istation apparatus of a :alling subscriber. When the subscriber at A removes his receiver from the switchhoolr, brushes 7/ and 7/ ol a finder engage terminals 6 and tv of the calling suhscl'ibcfis line and extend this line over conductors and c to brushes L and if of a selector. The subscriber on Operating the dial, places thes brushes I) and h in engagement with the terminals t and n of the trunk line leading to the desired connector switch.

\Vhcn the calling line has been extended to the connector, stepping relay 1 iscnergizcd over a circuit which may be traced from grounded battery, stepping relay 1, terminalfi, brush 7;, conductor 0, brush b, terminal t, conductor c, substationapparatus A, conductor a, terminal t, brush 1), conductor brush 7), terminal 6 right-hand winding of relay 1, to ground. Relay 1 is thereupon energized and attracts its armature. This closes a circuit for 'slow release relay 2, which may be traced from grounded battery, relay 2, front contact and armature of relay 1, to ground. Relay :2 attracts its arnuit'ures, When the calling subscriber opera-tee his calling dial or impulse sender .37, stepping relay 1 is momentarily del nergized,

but relay 2, which slow to dei ne-rgizc.holds 'up its armatures during these interruptions in its-energizing circuit. in response to these directive impulses, the switch brushes are steppcdjo the desired groups by the primary magnet 7 which is energized over a circuit extending from grounded battery. magnet 7, wiper 9, front contact and armature of relay 2, hack contact. and armature of relay 1 to ground. At the first interruption of stepping relay 1, a secoi-ul slow release relay 3 is energized over-a circuit which may be traced from grouruled battery, relay 3, front contact. and right-hand armature of relay 2, back contact and armature of relay 1, to ground. Relay 31 attracts its armatures and completes a circuit for escape magnet 4-, which may be trarcd-tro1n grounded hat tcry, magnet 4, hack contact and left-hand armatmfe o'tslow release relay 5, wiper (S-in its first position, front contact and left-hand armature of slow release relay 3, frontcontact and left-hand armature of relay 2, to ground. At the termination of the first series of directive impulses, relay 1' attracts its armature and thereby interrupts, at its back contact, the energizing circuit for the Second slow release relay 3. When relay 3 dei uergizcs. it interrupts, at its front contact and left-hand armatures, the energizing circuit of the escape magnet 4. This magnet defiucrgizcs and moves the sideswitch wipers into their second position.

'lhe-rciumu the calling subscriber sends another scrim oi directive impulses. and relays 2, 3-, and l'are energizcd as above descrilmd.

lit)

The secondary stepping magnet 8 is energized over a circuit which may be traced from grounded battery, steppingmagnet 8, wiper 9 in its second position, front contact and right-hand armature of relay 2, hack contact and armature of relay 1, to-ground.

At the termination of these. impulses, relay 1 again attracts its armature and also interrupts, at its back-contact. the energizing circuit for relay 3. Relay 3 then dei nergizes and interrupts. at its front contact and left-hand armature, the energizing circuit for escape magnet 4. Escape magnet 4- thereupon dei nergizes and moves the sidcswitch Wipers into position 3. even when the desired line is busy.

If the desired line is idle. the escape magnet is energized over a circuit? which may be traced from grounded hattery.'escape magnet 4, back contact and armature of relay 5, side switch wiper 6 in its third position. conductor 10, back contact and armature. of relay 11, conductor 12, back contact and right-hand armature of relay 3. front contact and left-hand armature of relay to ground. Escape magnet r attracts its arma turcs and at its innermost armature coin-- pletes a circuit over which ringing current is applied. This circuit extends from groiuub ed battery, .generator 13. relay 5, trout contact and innermostright-hand armature of magnet 4, conductor H. right-hand winding of relay 15, side-switch wiper 16 in its third position, connector brush 17. suhsta tion apparatus ll, ovcrthc. upper side of the line. brush l8, side-switch wiper 19 in its third position". conductor 20. eondmrtor 10, side-switch wiper (l in its third position. back contact and armature of relay .3. escape magnet t. to ground. When the called party at li removes his receiver. the marginal relay 5 of this circuit. is energized and interrupts the energizing circuit of escape. magmore into the 'lourlh'or talking position and .the (ltSll't-l-l connection is established between substations A and B.

If, however. the desired line is busy, this condition will be 'charactcrized by ground connection on tcsttcrminal 21 of the desired line. -Relay 11 will then be e-ncrgized over a. circuit extending from grounded battery. right-hand Winding of relay ll, side-switch wiper in its second position, and grounded test terminal 21-. Relay 11 thereupon attracts its armatures and. at its loft-handarmature establishes a locking air-- cuit for itself extending from grounded hat tery, left-hand \vi ling, front crmtact and armature of relay 1, conductor 12. right hand armature and back contact of relay 3, left-hand front. contact and armature of relay 2 to ground. When tluside-switch wiper moves into third position at the close of the last series of directing impulses, a

brush 23.

tactand lett hand armature of relay 2, to

ground. Here it'will he noted that, long as the lettvhand armature of relay 11 is attracted, the energizing circuit for escape magnet -t is open and its side-switch Wipers will continue to remain in their third post tion. While. the desired line is busy, busy tone is applied to the calling line lows: grounded battery. secondary winding fol-- of induction coil 29, side-switch wiper 3O 3I1 its third position, back contact and outermortright-hand armature of escape magnet in. conductor, 3'1 and the upper side of the line to substation A. v The interrupter '28, by means ot the primary winding of induction coil 29. ii'uluces an alternating current in the circuit just described. \Vhen; however, the desired line becomes tree the locking circuit through the right-hand winding of relay 11 is broken. but the energizing circuit for escape magnet t is still maintained open at the left-handarmature of relay 11. In order to complete. the energizing circuit o'f'the escape magnet i. it is about the deencrgization of the left-hand winding of the relay 11. This is brought about by the waiting party. The. Waiting necessary to bringparty in order tomomplete, the connection .with the desired line must t ansmit, after the desired line becomes idle, one or more impulses in addition to. the directive irr pulses which 'he has previously transmitted.

these impulses cause stepping relay 1,Which has previously been energized, to retract lts This e n'ipl-etes an energizing armature. circuit for slow release re-lay3 over a circuit previously described. Relay 3 is energized and. at itshack contact and righthand armature. opens the circuit which was previously described as extendingthrough the left-hand winding of relay 1.1. soon as relay 3 was energized, it attracted its outermost left-hand armature and completed an energizing circuit'for slow release relay 25. which may be traced from grounded. battery. relay front contact and outermost left hand armature of relay 3. side-switch wiper 2G in its third position. conductor 27. Front contact and armature ot' relay l. try-ground. \Vhen relay 25 was energized. it completed a. parallel locking circuit for the letthand armature of relay" '1 1 which may be traced mamas from grounded battery, left-hand winding of relay 11, front contact, and armature of relay 11, conductor 12, front contact and 'for the escape magnet, which circuit was previously described. Escape magnet 4 then attracts" its innermost left hand armature and ringing current is applied to the called partys line. When subscriber B respondsby removing; his receiver, the energizing circuit for escape magnet i is interrupted at marginal relay 5, which causes the sideswitch wipers to more into position 4-, as previously described.

It will be noted that no signal is transmitted to the waiting party to inform him when the desired line becomes idle. It will beunders'tood, however, that such a signal maybe employed ifdesired. The absence of tbesigl'lalto inform the waiting party that the desired line is free prevents the possibility of a doiirble commotion in case't'wo or more parties were awaiting connection with the same line, since it would be unusual for 'twowaii'iing particstodial at the same time. Under the present condition, subscribers may be instructed to operate their dials at intervals as long as the busy toneis continued.

At the termination of the conversation, the calling party at A replaces his receiwu. which action causes relay 1 to be decner gized. Release magmet 32 receives an energiliing impulse over the following circuit: grounded battery, agnet 32, off-normal contact 33, conductor 3 Jaclccontact and righthand armature of fl-clay 2, back contact and armature ofrelay l, to ground. Ma gnet completes the following locking circuit for itself: from grounded battery, magnet 32, ofi'-normalro1'itact'33. armature and front contact of magnet 32, to ground. 3 V switches indicatedby their brushes T35 and lid-and utilized in establishing the Connec- "normal positions by si'i'nilar. release magnets and. circuits which are iainlliar to those;

tic-1. to the connector are restored lo their skilled in the art and are" not herein shown ordescribed, y 3 U It;willbe nnderstoodthat the device herewin describedjz-ind illust'ratedTis; capable of x-man'y VHVIIH'UOHS andapphcations and that lab the scope of this invention is limited only by the appendedclaiins.

, 'lV-hat'is claimed is:

f In a telephone system, a g. .urality of iny ,connn'g- "operable st one of said inco s, outgoing line, a selectively chingdevlfce for. extending any Ii-g lines to the. outgoing and means jointly ctmtrolled over an incoming line and the outgoing line for actimting said relay.

3. In a telephone systei'n, incoming lines,

an outgoing line, a switch for extending any one of said incomin lines to said out going line, a relay control ing, upon its actuation, the SGlZUlCwOf the outgoing line by the switch, means jointly controlled and successively actuated, first over an outgoing line and then over the incoming line for actuating said relay.

In a telephone system, incoming lines, an outgoing line, a switch for extending any one of said incoming lines to said outgoing line, a relay controlling, upon its deiinen gization, the seizure of the outgoing line by the switch, an d means jointly controlled over an incoming and the outgoing line for actuating said relay. 7

5; In a telephone system, incoming lines, an outgoing line, a switch for extending any one of said incoming lines to said outgoing line, a relay controlling, upon its dcnergization, the seizure of the outgoing line by the switch, and means jointly controlledand successively actuated, first over an outgoing and then over the incoming line for actuating said relay.

6.. In a. telephone system, incoming lines, an outgoii'ig line, a switch for extending any one of said incoming lines to said outgoing line, a relay controlling, upon its actuation,

the seizure of the outgoing line' by said switch, said relay having two windings, and locking c1 nts including said windings, one of said cneurts being controlled over sald incoming line and the other'circuit being controlled over said outgoinv line. i

7. a telephone system, incoming lines,

. anmitgoing line, a switch for extending any one of said incoming lines to said outgoing line, an impulse device for directing the setting of said switch, an escape magnet, a

circuit for actuating said magnet, a' relay,

and a locking circuit for controlling said escape magnet including the winding of said relay and jointly controlled over said outgoing line and over said incoming line.

9. Ina telephone system, incoming lines, an outgoing line, a switch for extending any one of said incoming lines to said outgoing line, an impulse device for directing the setting of said switch, and means under the control of said impulse device for maintain ing said switch in operative relation to said outgoing line if that line is busy.

10. In a telephone system, incoming lines, an outgoing line, a switch for extending any one of said incoming lines to said outgoing line, an impulse device for directing the setting of said switch, and means including a circuit under the control of said impulse device for maintaining said switch in opera- .tive relation to said line if that line is busy and for actuating said switch to seize said line when it becomes idle.

11. In a telephone system, incoming lines, an outgoing line, a switch for extending any one of said incoming lines to said outgoing line, an impulse device for directing the setting of said switch, and means including locking circuit under the control of said impulse device ifoiimaiiitaining said switch in operative relation to said line while it is busy and for actuating said switch to seize said line when it becomes idle.

12. In a telephone system, incoming lines, an outgoing line, a switch for extending any one of said incoming lines to said outgoing line, an impulse device for directing thesetting of said switch, and means for control ling the seizure .of said outgoing line by said switch including a locking circuit completed when said line is busy and opened by any actuation of the impulse device after the busy condition is removed.

' 13. In a telephone system, incoming lines,-

an. outgoing line, a switch for extending any one of said incomin lines to said outgoing line, an impulse device fordirecting the get ting of said switch, and means' including a locking circuit having parallel branches which may be successively closed for maintaining said switch in operative relation to said outgoing line while it remains busy and for permitting one waiting incoming line to be connected to said line.

14. In a telephone system, incoming lines,

an outgoing line, a switch for extending any CHARLES. L. GOODRUM. 

